In the past, when wires which connect a wire harness with an internal circuit of a junction box are produced, pressure-contact terminals are usually crimped to the exposed core of the wire. These terminals are located in a connector which is fitted within a connector receptacle on the junction box. The terminals form an electrical connection via junction terminals to tabs on a busbar which is part of the internal circuit of the junction box. Customarily, the internal circuit is formed from single-core wires and pressure-contact terminals. In such a case, tabs (or junction terminals connected thereto), for forming electrical connections with external terminals, project into the connector in order to mate with the pressure-contact terminals therein. These terminals are connected to the ends of the wire harness.
Since the junction box and the wire harness are connected through a connector, it is necessary to crimp the pressure-contact terminals onto the ends of wires which are part of the wire harness. Moreover, these pressure-contact terminals must be inserted into a connector. As a result, many steps are necessary and a large number of parts (pressure-contact terminals and connectors) must be used. This increases cost and the likelihood of human error in assembly. Under normal circumstances, the terminals located in the connector are spaced apart from each other in a single row. This is wasteful of space, especially if there are a large number of such terminals.
In an attempt to solve the foregoing problems, the present Applicants proposed, in Japanese OPS 8-227738, a configuration for connecting connector-less electrical junction boxes and wire harnesses, as shown in FIG. 15 hereof. Wire harness W/H is composed of a plurality of wires W. These lead from the external circuit of wire harness W/H and the ends are inserted through wire insertion openings 1a into lower case 1 of junction box 10. A connector-less connection is formed between the cores of wires W and the conductors of the internal circuit by welding or the use of pressure-contact terminals 3. Thereafter, upper case 2 is affixed to lower case 1 to complete the assembly.
This configuration, however, suffers from certain drawbacks. The ends of the wires are inserted into the junction box and connected to the internal circuit. Hence, the junction box can be assembled only after the wires have been completely connected at the wire harness assembly workbench. In other words, if the wire harness is loosely bound (with the wires not completely assembled), it cannot be connected to a completed junction box containing the internal circuit. If it is necessary to first completely bind the wire harness at the wire harness assembly workbench, the entire operation becomes increasingly complex, resulting in a substantial cost increase.
Furthermore, in the foregoing arrangement, only the ends of the wire harness can be connected to the junction box. It is not possible to connect intermediate portions of the wire harness in this fashion. In addition, there is a danger that, since the wires inserted into the box are not fixed, any tension on the wire is liable to impair or destroy the connection with the internal circuit in the box. Hence, the reliability of the assembly is reduced.